Pipe-tapping device.



No 887,308; PATENTED MAY 12, 1908.

. J. H; B. BRYAN.

PIPE TAPPING DEVICE.

APPLICATION FILED MAR. 6. 1906. I

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THE NORRIS PETERS co.. \v snma1orv, u. k,

,PATENTED MAY 12, 1908.

JQH. B. BRYAN. PIPE TAPPING DEVICE.

APPLICATION FILED MARJ6, 1906.

2 SHEETS-SHEET 2.

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UNITED STATES PATENT OFFTDE'.

JOHN H. B. BRYAN, OF BUFFALO,

NEW YORK, ASSIGNOR, BY DIRECT AND MESNE ASSIGN- MENTS, OF ONE-THIRD TONICHOLAS J. KELLY AND ONE-THIRD TO NORA KELLY, OF

BUFFALO, NEW YORK.

Specification of Letters Patent.

PIPE-TAPPING DEVICE.

Patented May 12, 1908.

with a branch pipe and more particularly to a device of this characterfor making such connections with the main pipe or line of a water systemwithout disturbing the use' of the main pipe or interfering with thewater system while such connection is being made. A device for thispurpose is shown in the prior application for patent filed by myself onthe 11th day of January, 1906, and numbered 295,527. The constructionshown in this prior application is such that the same is incapable oftapping more than one size opening in the main pipe.

The object of the present invention is to provide a pipe tapping devicewhich is so constructed that but few changes are necessary to permit ofusing the device for producmg openings of different diameters.

In the accompanying drawings consisting of two she'ets:Figure 1 is a topplan view partly in section, of my improved pipe tap ping device inposition for producing an opening in a main pipe whereby the same isconnected with a branch pipe. Figs. 2, 3 and 4 are vertical crosssections taken in lines 22, 33, and 4-4, Fig. 1 respectively. Fig. 5 isa longitudinal section of the tapping device applied toa main and branchpipe. Figs. 6, 7 and 8 are cross sections taken in the correspondinglynumbered lines in Fig. 5. Fig. 9 is a longitudinal section taken in line99, Fig. 7. Fig. 10 is a fragmentary view of the cutter carrier and oneof the cutters or teeth thereon. Fig. 11 is an end view of the same.

Similar letters of reference indicate corre sponding parts throughoutthe several views.

A represents the main pipe or line of a water distributing system whichmay form either the suction part or the delivery part of the main and Bis the branch pipe connected therewith.

The connection between the main pipe and the branch pipe is primarilyeffected by means of a coupling or fitting O, the head of which ispreferably divided diametrically lengthwise into two sections a, c whichare applied to opposite sides of the main pipe and held in place bymeans of wedging clips or bars 0 which engage with opposing flanges 0formed lengthwise on the opposing longitudinal edges of the headsections. Any other suitable means may be employed for holding the headsections of the fitting on the main pipe.

The latter branch 0 of the fitting may be arranged at any desired anglerelatively to its head and the main pipe, but in the drawings the sameis shown at an angle of forty five degrees relatively thereto.

D represents the body of a main gate valve having the front end of itspassage or water way connected with the inner or front end of thefitting branch 0 E represents a short section of pipe which is connectedat its front end with the rear end of the valve body D, this sectiontogether with the fitting branch 0 and the valve body D being axially inline. The fitting branch and valve body form the initial portion of thebranch pipe B which is to be permanently connected with the main pipeand the pipe section E may also, if desired, form a permanent part ofthe branch pipe but it is preferable to remove the same together withparts of the tapping device with which it is connected.

F represents a head cover or closure secured to the outer end of thepipe section E for closing the same and preventing the escape of waterwhile cutting the opening in the main pipe within the fitting branch.This opening is formed by producing a circular kerf f in the main pipeof substantially the same diameter as the bore of the fitting branch,thereby severing or cutting out a circular section or patch f which issubsequently removed. The means shown in the drawings for producing thiskerf consists of an annular series of cutters or milling teeth 9 whichrotate close to the bore of the fitting branch about an aXis whichcoincides with that of the fitting branch, valve body and pipe sectionF. These cutters are supported by a rotary and longitudinal movablecarrier consisting of a cylindrical body G which is opened at its frontend and provided at its rear end with a head 9 The cutter teeth 9project lengthwise forward from thefront end of the carrier body and aresecured thereto in any suitable manner but if desired these teeth may beformed integral with said body.

In order to permit the cutter teeth to clear themselves and preventbinding or cramping as they enter the metal of the main pipe each ofthese teeth tapers from its wide front end toward its narrow rear endand projects radially outwardly beyond the periphery of the carrier bodyand inwardly beyond the bore thereof, as shown in Figs. 5 and 11, sothat the carrier body-is free to follow into the kerf behind the cutterteeth.

In order to hold the cutter body accurately in a central position withinthe fitting branch during the cutting operation, a guide sleeve H isprovided which is interposed between the outer side or periphery of thecarrier body and the adjacent part of the fitting branch and gate valvepassage. This guide sleeve is of such thickness that it holds the outerportions of the cutter teeth out of contact with the bore of the'fittingbranch and serves to hold the cutter carrier accurately in a centralposition while the latter is being rotated for producing the kerf andalso while the same is being fed forward as the cutting operationprogresses.

h represents a tubular shank passing axially through an opening in thehead F, and connected at its front end with a head h at the rear end ofthe guide sleeve. Within this shank is arranged a longitudinal cuttershaft I which is connected at its inner or front end with the head ofthe cutter body by a screw joint, as shown in Fig. 5, or by any othersuitable means. Leakage between the head F and the tubular shank isprevented by means of a stuffing box it arranged on said head. For thesame purpose a stuffing box t is arranged in the enlarged front part ofthe shank around the cutter shaft.

Various means may be employed for moving the cutter carrier and itsguide sleeve axially in the fitting branch, valve passage and pipesection E and also rotating the cutter carrier during the operation oftapping the main pipe.

J represents a carriage which is movable lengthwise of the axis of thecutter carrier and the branch pipe adjacent to the outer end of the pipesection E. This carriage is guided by means of two parallel rods or barsK, K arranged lengthwise on opposite sides of said axis and receivingeyes or sleeves on opposite sides of the carriage by which the latter isslidably mounted on said bars. The

front ends of these bars are preferably supported by means of reducedscrew shanks k formed thereon and passing through openings in themarginal portion of the head F and a flange k formed on the outer end ofthe pipe section E and screw nuts k applied to said shanks in front ofthe said flange.

.The rear ends of these bars are in like manner secured to the standardor pedestal L. The outer end of the tubular shank h is rigidly connectedwith the front side of the carriage so that the guide sleeve H iscompelled to move lengthwise with the carriage. The longitudinalmovement of the carriage and the parts connected therewith may beeffected in any suitable way but preferably by means of two upwardlyconverging shafts M, M journaled in bearings on the carriage andprovided at their lower ends with gear pinions m which mesh with gearracks m formed on the guide bars, intermeshing bevel gear wheels marranged on the upper ends of said shafts and a hand wheel 1% applied toone of them. Upon turning this hand wheel in one direction or the otherboth converging shafts are turned in unison and by their pinionsengaging with the gear racks,

causing the carriage and connecting parts to move forward or backwardwithout cramping or binding any of them. In order to hold these partsagainst backing up after they have been moved into their forward oroperative position, a detent or holding device is provided whichpreferably consists of a ratchet wheel N secured to the shaft M and apawl n mounted on the carriage and en gaging with the teeth of theratchet wheel N. This pawl is moved into an inoperative position when itis desired to move the carriage and connecting parts backwardly.

0 represents a gear wheel j ournaled on the carriage but compelled tomove lengthwise therewith. This is preferably effected by constructingthe carriage in two sections y", 3' between which the wheel is arrangedand which have bearings receiving the ends of the hub of the'gear wheel0. The cutter shaft I passes axially through the hub of the gear wheel 0and is operatively connected therewith by splines 0 whereby the cuttershaft is compelled to turn with the gear wheel but normally is free tomove lengthwise independent thereof.

P represents a horizontal counter shaft arranged lengthwise above thecutter shaft and journaled at its frontand rear ends in bearings formedin the upper parts of the carriage J and the pedestal but held againstaxial movement in the carriage. Between the upper parts of the carriagesections the countershaft has secured thereto a pinion p which mesheswith the upper part of the gear wheel 0. At its rear end the countershaft is provided with a beveled gear wheel Q which meshes with abeveled gear pinion g. The latter is secured to the inner end of atransverse driving shaft which is journaled transversely in a bearing onthe pedestal and which may be rotated by means of a driving wheel Rsecured to the outer end of the driving shaft g and provided with acrank or handle r. The rotary movement of the driving shaft g istransmitted successively by the pinion g, gear wheel Q, counter shaft Pand gear wheels 1), O to the cutter shaft when the tapping device is inuse.

S represents a feed screw and S a screw nut which form part of themechanism whereby the cutter and its shaft are moved axially. The feedscrew is of hollow or tubular form and receives the outer end of thecutter shaft. The screw nut S engages with the thread of the feed screwand is journaled in a bearing 8 in the central portion of the pedestalbut is held against aXial movement therein by means of a head 8 arrangedon the front end of the screw nut and bearing against the front side ofthe bearing 8 and a retaining nut 8 arranged at opposite ends of thescrew nut and engaging with the opposite end of said bearing.

During the first part of the cutting operation it is desirable to effectthe forward feed of the cutter carrier by hand in order to get thecutter started properly but after the beginning ofthe cutting operationthe feeding of the cutter carrier is effected automatically.

To permit of feeding the cutter carrier by hand the screw nut S is heldstationary in the pedestal, the feed screw S is held against axialmovement relatively to the cutter. shaft by securing collars 19 p to thecutter shaft at the front and rear ends of the feed screw, and a handwheel 8 is secured to the rear end of the feed screw for/manipulatingthe same manually. Upon turning the hand wheel forwardly in thiscondition of the parts the feed screw working against the nut S on thepedestal causes the cutter shaft to be advanced together with the cuttercarrier at the same time that these parts are being turned.

The mechanism whereby the cutter carrier and connecting parts may beautomatically moved lengthwise is constructed as follows: T represents atransverse locking or a holding bar or arm which is pivoted at one endon one of the guide bars K and adapted to rest with its opposite end onthe other guide bar while its central part is provided with two jaws t,t which engage with the recesses a in opposite sides of a locking head Uarranged at the front end of the feed screw, the bottoms of saidrecesses being flat, as shown in Fig. 4. By this construction, therecesses u when engaged by the jaws of the holding bar prevent the feedscrew from turning and the holding arm is compelled to move lengthwisewith the feed screw during which movement the holding bar slideslengthwise on the guide arm K to which it is pivoted. V- represents aratchet wheel or rim formed on or secured to the front end of the screwnut S and v represents an oscillating ratchet or feed lever journaledupon the feed nut S between the ratchet wheel and the front side of thepedestal. One arm of this feed lever has pivoted thereto a double endedpawl V either one of which may be held yieldingly in engagement with theteeth of the ratchet wheel V by means of a spring pressed plunger 12arranged on one arm of the feed lever and engaging with one side or theother of the heel '0 formed on said pawl adjacent to the pivot thereof.W represents an eccentric secured to the countershaft and having itssurrounding strap to adjustably connected with the other arm of the feedlever by means of a connecting rod w and a bolt to passing through saidrod and a radial slot 10 in said arm, as shown in Fig. 3. -During therotation of the countershaft its eccentric oscillates the feed lever vand the latter by engaging one end or the other of its pawl with theratchet wheel turns the feed nut intermittently causing the feed screwto be moved lengthwise together with the parts connected therewith.

In producing the kerf in the main pipe which separates the section orpatch f of the main pipe to be removed it is necessary to retain controlof said patch in order to prevent the same from being carried away bythe water and interfere with the distributing system. For this purposean opening a: is previously bored into the central part of the patchwhich is to be removed by the dev vice shown in the co-pendingapplication for Letters Patent No. 296,634 filed by myself, on the 18thday of January, 1906. Into this opening is firmly secured the frontendof a retaining rod X preferably by tapering this end of the rod anddriving the same firmly into said opening. This rod is arranged axiallywithin the cutter shaft which latter is made hollow or tubular for thispurpose and the same projects with its rear end beyond the rear end ofthe cutter shaft to permit of manipulating the same. For preventingleakage between the retaining rod and the cutter shaft a stuffing box 00is arranged at this end of the shaft. The retaining rod is preventedfrom being drawn inwardly to gether with the patch secured thereto bymeans of a collar x secured to the outer part thereof and engaging withthe gland of the stuffing box 90 or the adjacent part of the cuttershaft.

Instead of turning the driving shaft 9 by hand this may be effected bypower derived from the pressure of the water in the main. For thispurpose the wheel R may be driven by a belt y from the pulley 1 of awater motor z, the retaining rod X being made hollow or tubular so as topermit water to be drawn off through the same, and the outer end of thisrod being connected with the motor by means of a pipe 2 containing avalve 2 for controlling the water supply.

Assuming that the central opening x has been reviously bored or drilledinto the patch by means of the boring device of the co-pendingapplication No. 296,634 above referred to and that the gate 01 of thevalve body D is closed, the operation of cutting out the patch from themain pipe for producing a full opening between the main pipe and thebranch pipe by the use of the present tapping device is as follows :Theseveral parts of the tapping device are so assembled that the feed screwis at its outermost position in the feed nut, the carriage is in itsoutermost position on the guide bars, the pipe section E and head it areconnected with the front ends of the guide bars K, the guide sleeve Hand the cutter carrier are in their rearmost position within thepipesection E, the holding arm is disengaged from the locking head U and theretaining rod X is inserted in the hollow cutter shaft. The front end ofthe pipe section E is now secured to the outer or rear end of the valvebody D by bolts or otherwise so that this pipe section forms a closedextension of the passage way of the main valve. The gate at of thelatter is now opened permitting the water to pass from the main pipesuccessively through the opening x the fitting branch and the main valvebody into the pipe section E. By 0 ening the gate 61 an unobstructedpath is a so formed which permits of moving the %arts of the tappingdevice within the section forwardly into engagement with the main pipeWithout however permitting the escape of any water. The retaining rod Xmaybe moved forward simultaneously with the cutter carrier while in suchposition that its front end is inserted in the opening w of the patchbefore the cutter mechanism engages the main pipe but if desired theretaining rod may be first pushed forward until its front end is firmlywedged in the opening m and then the cutter carrier and its guide sleevemay be moved forward'close to the main pipe ready to begin the cuttingoperation. This forward movement of the retaining rod can be easilyeffected by hand as the area which the same exposes to the waterpressure is not sufficient to offer any considerable resistance. Thecutter carrier and its guide sleeve however present a considerable areato the water pressure and the heads of these parts are thereforeprovided with openings 9 h which permit the water to pass through thesame so that the water pressure against opposite sides of these parts isneutralized, thereby permitting the same to be moved forward easily intotheir operative positions. This forward movement of I the parts isproduced by turning the hand cutter carrier and guide sleeve havereached the beginning of their operative position, as shown in Fig. 5,the cutter shaft is rotated either by hand power applied to the crank 1'or by water power derived from the motor or if desired by applying aratchet lever applied to the flat sided front end 10 of t countershaft.For starting the cutting operation the cutter carrier is fed forwardslowly by turning the feed screw in the roper direction by means of thehand whedl 8 the feed nut being held stationary at this time, and thepawl if being thrown out of engagement with the ratchet wheel V. Afterthe cutting operation has been started the holding arm T is engaged witha locking head U of the feed screw for holding the latter againstturning and the pawl v is turned with the proper end in engagement withthe ratchet wheel V for causing the feed. nut to be turned in thedirection for moving the feed screw, the cutter shaft and the cuttercarrier forwardly. The speed of this forward feed must be variedaccording to the character of the main pipe which is being cut and maybe regulated by moving the rod to inwardly or outwardly in the slot w ofthe feed lever 'U for obtaining the required feeding action of thecutter. While thus feeding the cutter carrier forwardly the cutter guideremains behind with its front edge adjacent to the periphery of the mainpipe so as to support the cutter carrier as close as possible to thecutting line. Inasmuch as the backward rotation of the cutter carrier isliable to injure or break off the cutter teeth which present an abruptfront side and an inclined rear side, as shown in Fig. 10, means areprovided for preventing such an occurrence the same preferablyconsisting in mounting the driving gear wheel R loosely on the mainshaft g and operatively connecting the same therewith by a pawl 1"arranged on the driving wheel and engaging with a ratchet wheel r on thedriving shaft, as shown in Figs. 1, 3 and 11 whereby the cutter iscompelled to turn forwardly with the driving wheel but the latter whenmoved backwardly does not affect the cutter.

After the patch has been cut out the same is first drawn outwardlywithin the cutter carrier by means of the retaining rod X and then thecutter carrier and guide sleeve are retracted into their outer positionswithin the pipe section E. The gate of of the main valve may now beclosed permitting the front end of the pipe section E to be removed fromthe gate valve together with the parts mounted thereon after which theextension of the branch pipe E from the outer side of the gate valve maybe effected in the usual manner.

The arts of the tapping device may be manipu ated in various ways forefiecting the retraction of the cutter carrier and the guide sleeve intothe pipe sectionE preparatory to closing the gate d of the main valve.One way of doing this is to manipulate the parts whereby the guidesleeve and cutter carrier are moved in the opposite direction from thatjust described but this method is comparatively slow. For effecting aquick retraction of these parts it is preferable to first back the feedscrew S outwardly by means of the hand wheel 8 until the cutter carrierhas been withdrawn into its guide sleeve after which the cutter shaft iscoupled with the carriage so as to be compelled to move outwardly withthe same and the guide sleeve by means of a clamping screw 0 passingthrough one end of the hub of the gear wheel 0 and set tight against thecutter shaft at the time for effecting such withdrawal. This screw isdisengaged from the cutter shaft when the cutter is in operation.

If it is desired to make the machine comparatively short the length ofthe feed screw S may be reduced in length and in that case this screwafter its feeding action in one direction has been exhausted may beshifted into the opposite position independent of the cutter shaft byfirst loosening the collars 19 p", then reversing the rotation of thefeed screw S to the end of its movement in the opposite direction andthen refastening the collars 19 p to the cutter shaft at opposite endsof the feed screw in its shifted position when the shifting effect ofthis screw may be repeated.

When this tool or device is to be used for tapping openings of differentdiameters in a main pipe it is only necessary to substitute a cuttercarrier, guide sleeve and pipe extension E of larger or smaller diameterfor the one previously used, the other parts remaining in the sameposition and operating as before described.

I claim as my invention 1. A tapping device for connecting a main pipewith a branch pi e, comprising a cylindrical carrier of smal er diameterthan the bore of said branch pipe and adapted to be rotated and alsomoved axially therein, cutters arranged at the front end of said carrierand projecting laterally beyond the periphery of the carrier and adaptedto produce an opening in said main pipe of a diameter approximately thesame as the bore of the branch pipe, a guide sleeve fitting with itsbore around the periphery of the carrier while its periphery is arrangedbeyond said cutters and is adapted to bear against the bore of thebranch pipe, and means for moving said carrier and sleeve axiallytogether or one independent of the other, substantially as set forth.

2. A tapping device for connecting a main pipe with a branch pipecomprising a rotatable cutter carrier adapted to be placed in saidbranch pipe, a shaft connected with said car rier, a gear wheel splinedto said shaft, a longitudinally movable carriage on which said gearwheel is journaled, a driving mechanism operatively connected with saidgear wheel, and means for connecting and disconnecting said carriage andshaft so as to permit of moving the same lengthwise together or permitthe carriage to move independently of the shaft, substantially as setforth.

3. A tapping device for connecting a main pipe with a branch pipecomprising a rotatable cutter carrier adapted to be placed in saidbranch pipe, a shaft connected with said carrier, a gear wheel splinedto said shaft, a longitudinally movable carriage on which said gearwheel is journaled and which is composed of two sections pivotallysupporting said gear wheel at opposite ends of its hub, a drivingmechanism operatively connected with said gear wheel, and means forconnecting and disconnecting said carriage and shaft so as to permit ofmoving the same lengthwise together or permit the carriage to moveindependently of the shaft, substantially as set forth.

4. A tapping device for connecting a main pipe with a branch pipecomprising a rotary cutter carrier adapted to be placed in said branchpipe, a shaft connected with said cutter carrier, a driving mechanismfor said shaft comprising a gear wheel splined on said shaft, alongitudinally movable carriage on which said gear wheel is journaled, adriving pinion mounted on the carriage and meshing with the gear wheel,guide bars in which said carriage is slidably supported, and means forconnecting and disconnecting said carriage and shaft and. causing thesame to move axially together or permitting one to move aXiallyindependently of the other, substantially as set forth.

5. A tapping device for connecting a main pipe with a branch pipecomprising a rotary cutter carrier adapted to be placed in said branchpipe, a shaft connected with said cutter carrier, a driving mechanismfor said shaft comprising a gear wheel splined on said shaft, alongitudinally movable carriage on which said gear wheel is journaled, adriving pinion mounted on the carriage and meshing with the gear wheel,guide bars on which said carriage is slidably supported, means formoving said carriage lengthwise of said bars comprising gear racksarranged on said bars, and pinions mounted on said carriage and meshingwith said gear racks, and means for connecting and disconnecting saidcarriage and shaft and causing the same to move axially together orpermitting one to move aXially independently of the other substantiallyas set forth.

6. A tapping device for connecting a main pipe with a branch pipecomprising a rotary cutter carrier adapted to be placed in said branchpipe, a shaft connected with said cutter carrier, a driving mechanismfor said shaft comprising a gear wheel splined on said shaft, alongitudinally movable carriage on which said gear wheel is mounted, adriving pinion mounted on the carriage and meshing with the gear wheel,guide bars arranged lengthwise on opposite sides of said shaft andsupporting the ends of said carriage, means for moving said carriagelengthwise on said bars consisting of gear racks arranged on said bars,upwardly converging shafts journaled on said carriage, pinions arrangedon the lower ends of said converging shafts and meshing with said gearracks, intermeshing gear wheels arranged on the upper ends of theconverging shafts, and a handle or wheel arranged on one of theconverging shafts, and means for connecting and disconnecting saidcarriage and shaft and causing the same to move axially together orpermitting one to move axially independently of the other substantiallyas set forth.

7. A tapping device for connecting a main pipe with a branch pipecomprising a rotary cutter carrier adapted to be placed in said branchpipe, a shaft connected with said cutter carrier, a driving mechanismfor said shaft comprising a gear wheel splined on said shaft alongitudinally movable carriage on which said gear wheel is journaled, adriving pinion mounted on the carriage and meshing with the gear wheel,means for connecting and disconnecting said carriage and shaft forcausing said shaft and carriage to move together axially or permit theseparts to move axially independently of each other, substantially as setforth.

8. A tapping device for connecting a main pipe with a branch pipecomprising a rotary cutter carrier adapted to be placed in said branchpipe, a shaft connected with said cutter carrier, a driving mechanismfor said shaft comprising a gear wheel splined on said shaft, alongitudinally movable carriage on which said gear wheel is j ournaled,a driving pinion mounted on the carriage and meshing with the gearwheel, means for connecting or disconnecting said carriage and shaft,consisting of a clamping screw arranged on the hub of said gear wheeland adapted to be engaged with said shaft for causing said cuttercarrier to move lengthwise with said carriage, or permitting these partsto move independently of each other, substantially as set forth.

9. A tapping device for connecting a main plpe with a branch ipe,comprising a cutter carrier adapted to e laced in said branch pipe, ashaft connecte with said carrier, an

o erating mechanism connected with said s aft, a guide sleeve adapted tobe interposed between said cutter carrier and the bore of the branchpipe, a tubular shank surrounding said shaft and connected with saidguide sleeve, and a shifting device connected with said shank,substantially as set forth.

10. A tapping device for connecting a main pipe w1th a branch pipe comrising a cutter carrier adapted to be place in said branch pipe, a shaftconnected with said car rier, a guide sleeve adapted to be interposedbetween said carrier and branch ipe, a tubular shank surrounding saidsha 't and connected with said sleeve, and a carriage adapted to beconnected or disconnected with said shank, substantially as set forth.

11. A tapping device for connecting a main pipe with a branch pi ecomprising a rotary cutter carrier adapte to be inserted in said branchpipe, a cutter shaft connected with said carrier, and means for movingsaid shaft axially comprising a rotatable feed screw operativelyconnected with the cutter shaft, a rotatable screw nut engaging withsaid feed screw, means for holding said screw against turning orreleasing the same to permit turning thereof, and means for turning saidfeed screw and holding said nut against turning substantially as setforth.

12. A tapping device for connecting a main pipe w1th a branch pipecomprising a rotary cutter carrier adapted to be inserted in said branchpipe, a cutter shaft connected with said carrier and means for movingsaid shaft axially comprising a tubular feed.

screw rotatable on the cutter shaft, means for holding said feed screwagainst turning or releasing the same to permit turning thereof, arotatable screw nut adapted to be held stationary and engaging withsaid'feed screw, and a hand wheel secured to said feed screw for turningthe latter, substantially as set forth.

13. A tapping device for connecting a main pipe w1th a branch pi ecomprising a rotary cutter carrier adapted to be inserted in said branchpipe, a cutter shaft connected with said carrier and means for movingsaid shaft axially comprising a feed screw mounted on said cutter shaft,means for compelling said screwand shaft to move in unison axially, arotary screw nut journaled in a stationary bearing and engaging withsaid feed screw, means for holding said screw nut against rotation orpermitting rotation thereof, and means for holding said feed screwagainst rotation or permitting rotation thereof, and means for rotatingeither the feed screw or the screw nut, substantially as set forth.

14. A tapping device for connecting a main pipe witha branch pipecomprising a rotary cutter carrier adapted to be inserted in said branchpipe, a cutter shaft connected with said carrier, and means for movingsaid shaft axially comprising a feed screw mounted on said cutter shaft,means for compelling said screw and shaft to move in unison axially, arotatable screw nut mounted in a stationary bearing and engaging withsaid feed screw, means for rotating said feed screw independently ofsaid shaft, and means for holding said feed screw against rotation,consisting of a head arranged on said feed screw and provided onopposite sides with recesses having fiat bottoms, and a holding armhaving a pair of aws entering said recesses and engaging the bottomsthereof, substantially as set forth.

15. A tapping device for connecting a main pipe with a branchpipecomprising arotary cutter carrier adapted to be inserted in said branchpipe, a cutter shaft connected with said carrier, and means for movingsaid shaft aXially comprising a feed screw mounted on said cutter shaft,means for compelling said screw and shaft to move in unison aXi ally, arotary screw nut journaled in a stationary bearing and engaging withsaid feed screw, means for rotating said feed screw independently ofsaid shaft, and means for holding said feed screw against rotation,consisting of a head arranged on said feed screw and provided onopposits sides with recesses having fiat bottoms, stationary guide barsarranged lengthwise on opposite sides of the cutter shaft and feedscrew, a transverse holding arm pivoted at one end on one guide bar andresting at its opposite end on the other guide bar, and apair of jawsarranged on the central part of said arm and engaging with saidrecesses, substantially as set forth.

16. A tapping device for connecting a main pipe with a branch pipecomprising a rotary cutter carrier adapted to be inserted in the branchpipe, a hollow cutter shaft connected with the cutter carrier, a tubularretaining rod arranged in said shaft and adapted to be inserted in anopening in the main pipe, and means for, rotating said cutter shaft andcarrier comprising a water motor which is supplied by said tubularretaining rod, substantially as set forth.

Witness my hand this 29th day of January, 1906.

JOHN H. B. BRYAN.

